DZIEMBOWSKI, S. The Fixpoint Bounded-Variable Queries are PSPACE-Complete. BRICS Report Series, [S. l.], v. 3, n. 41, 1996. DOI: 10.7146/brics.v3i41.20023. Disponível em: https://tidsskrift.dk/brics/article/view/20023. Acesso em: 27 apr. 2024.